My grandmother's farm, in the family since 1840 and still in the family is only 2 miles below the MI border in northern OH, and many beautiful NA atifacts have been found there over years of plowing. It is right below Hillsdale county, MI. I am sure there must be great NA artifacts found in your area but those items you show are not artifacts. I just looked up museums in southern MI and the MI History Center in Lansing has a section on prehistoric MI and artifacts from that era. I suggest you go over there and study these artifacts and educate yourself in what they look like.